Power-Programmierung/CD1.mdf/basic/library/gwbasic/misbasic/heatloss.doc

Text File | 1988-09-26 | 5.3 KB | 86 lines

                 ARE YOUR HEATING DOLLARS GOING OUT THE WINDOW?

               Learn Cost-Efficient Insulation with This Program

     A READER WRITTEN PROGRAM BY BERT GUSTAVSON :FAMILY COMPUTING VOL1 NUM1

                  CONVERTED FOR PC BY BRUCE AND DEBBIE ALMEIDA

     Winters in Rochester,New York, can be formidable.  In a normal winter, the
temperature can stay below freezing from mid-December until early March, with a
few days of thaw to provide brief respite from the cold.  Winds often whip  the
snow  into  drifts,  and slippery roads and poor visibility due to the swirling
snow make driving hazardous.

     In the winter of 1976-77 when my fuel prices began skyrocketing, I started
upgrading  the heating efficiency of my house.  I began by adding insulation in
the ceiling, building enclosed vestibules for the front and back  entrances  of
the  house, and insulating around the water heater and all hot-water pipes from
the heater to the faucets.

     Then I put my TI-99/4A to work to determine where my heating dollars  were
going.    The  accompanying  program,  which I wrote in TI BASIC ,will tell you
which parts of the house are allowing the greatest amount of heat to escape and
how  much  money  you  can  save  by  the  investments in insulation, caulking,
weatherstripping, etc., that you are considering.   By  comparing  the  figures
with  the  cost  of improvements, you can determine which potential investments
would be most cost effective.

     Of course, this information is valuable whether you have  yet  to  do  any
weatherizing  or have already begun and are considering further steps.  (If you
do choose to do insulation yourself, be  sure  you  learn  proper  installation
techniques or you will not get the result you want.)

     As is true with most calculations performed on a home computer, you  could
accomplish the same thing with a calculator, with an abacus, or with plain old-
fashioned arithmetic using a pencil and paper.   The  advantage  of  writing  a
computer  program to do the work is that you can change the numbers and quickly
get answers for a variety of situations:  How much will I gain by  changing  to
double-glazed  windows?    To  triple-glazed?   What about adding six inches of
insulation in the attic?  Twelve inches?  Eighteen?

     Before you run the program-in fact, before you start to add insulation  or
do  any  other weatherization-you should know what your present conditions are.
The first thing you should do is to find out how much insulation you now  have.
In  the case of an unfinished attic that's fairly easy:  Just go into the attic
with a ruler and  measure  the  depth  of  the  insulation.    The  R-value  of
fiberglass  insulation  is  roughly  R-3 per inch of insulation.  (R-value is a
measure of the resistance of a  material  to  the  flow  of  heat.)  Fiberglass
insulation  is  available  in  standard thicknesses of 3 1/2 inches(R-11) and 6
inches (R-22).  R-values of loose-fill cellulose insulation (made of  ground-up
newspapers treated with a fire-retardant chemical) are slightly higher per inch
of thickness.

     Determining the R-value of insulation in the walls of an existing house is
a bit tougher.  You can probe into the wall cavity next to an electrical outlet
to find out whether there is any insulation there:  TURN  OFF  THE  ELECTRICITY
BEFORE  ATTEMPTING  TO PROBE INTO THE WALL CAVITY.  In an older house- one with
the old standard of 2-by-4 wall studs- the chances  are  the  walls  have  R-11
insulation.    Your  local  utility  company, heating oil supplier, or building
materials dealer can help you determine the R-values of your home.

     You can keep a better check on your heat use if you keep accurate  records
of your heating bills and fuel consumption.  If you heat with natural gas, your
monthly bill will show the amount of fuel used (usually in  hundreds  of  cubic
feet).    Electric  bills  will  show consumption in kilowatt hours (kwh).  Oil
bills show the number of gallons delivered.

     Before running the heat-loss calculation program, you also  will  need  to
know  the  areas of the various elements of your house.  In a simple house, the
area of the ceiling is just the width of the house multiplied  by  the  length.
The area of the walls is the perimeter of the house multiplied by the height of
the walls from floor to ceiling.  Measure windows  and  doors  from  casing  to
casing  on  the  sides and from top to sill.  Multiply these two figures to get
the area of each window and door.  Add all the areas together to get the  total
window and door area.  The volume of a heated space is the floor area times the
ceiling height.  Descriptions in the program will  help  you  decide  the  air-
infiltration  factor,  that  is, the airtightness of your house.  Older, drafty
houses can have a complete change of air (an air exchange) every five  minutes,
while the new superinsulated houses might have one exchange per hour.

     When answering the glazing questions, if not all the windows have the same
glazing,  use an average figure.  For example, if only half of your windows had
storm windows over them (and if all your windows were  approximately  the  same
size)  ,  you  would give your present glazing as 1.5.  You can count a typical
solid wood door with a few single panes of glass as double glazing.